Regenerating Longleaf Pine on Hydric Soils: Short- and Long-term Effects on Native Ground-Layer Vegetation

Abstract : Across the southeastern United States longleaf pine woodlands support a wide range of military training activities and provide suitable habitat for diverse communities of plants and animals, including remarkable numbers of threatened, endangered, and at-risk plant and animal species (TERS). As a result of historical land uses, large areas previously dominated by longleaf pine now support different forest types, especially on wetter more productive sites, and active forest management is required to restore them. Restoring longleaf pine on poorly drained sites where there is no remaining natural seed source, and doing so without further losses of any remaining native herbaceous vegetation, is arguably one of the most difficult challenges to restoration ecologists. This project addressed that problem. Methods to establish longleaf pines on well-drained sites are well-understood, but not so on poorly drained sites that occupy much of the outer coastal plain, including Marine Corps Base Camp Lejeune, North Carolina. On wetter sites foresters typically rely on intensive management actions to prepare the sites for planting trees. Effective site preparation methods minimize seedling mortality and promote early, rapid growth, but also potentially reduce the herbaceous component of the ground layer plant community. Vigorous herbaceous ground layer that covers at least 40% of the area is a defining standard for high quality red-cockaded woodpecker foraging habitat (US FWS 2003). In addition to direct effects of plantation establishment, longer term effects on habitat quality accrue through time as the new forest develops. These effects also are not well documented for poorly drained sites, nor are the driving ecological processes known.